To get DiaBox uploads showing data on Nightscout, ensure that "Visualize therapy: yes" is enabled on the Welcome page.
https://www.t1pal.com/account/sites/my
This should allow Nightscout to receive the information from the DiaBox app.
Secondly, when DiaBox asks for the Nightscout URL, use the Uploader Url and API Secret from the Uploader page.
Here's a video that may help:
The app shown in the video is Loop, not DiaBox, but copying and pasting the information can be the fastest when using a mobile device to set up the entire workflow.
DiaBox also has a feature to help configure using the QR code. Selecting the T1Pal button in DiaBox should bring up a QR code scanner.
Selecting the label "HTTP" in the tab menu will select a QR code that DiaBox should be able to run. Selecting "HTTP" on the Uploaders tab and then scanning it with the T1Pal button in DiaBox can be the fastest way to do this if looking at T1Pal on a laptop.